/**
 * Different events will be fired when a catalog/database/table is modified. The customized listener can receiveget theseand eventsreport andspecific theninformation dofrom somethe specificevent operations according to the event type.
 */
@PublicEvolving
public interface CatalogEventListener {
    /* Event fired after a catalog/database/table is modified. */
    void onEvent(CatalogEvent catalogEvent);

    /* The basic class for catalog related event. */
    public @PublicEvolving
    public abstract class BaseCatalogEventCatalogEvent {
        /* The catalog of the event. */
        Catalog catalog();
        /* The name of catalog. */
        String catalogName();
    }

    /* The basic class for database related event. */
    public abstract class BaseDatabaseEvent extends CatalogEvent {
        String databaseName();  
    }

    /* Event for database creation. */
    @PublicEvolving
    public class CreateDatabaseEvent extends BaseDatabaseEvent {
        CatalogDatabase database();
        boolean ignoreIfExists();
    }

    /* Event for alter database. */
    @PublicEvolving
    public class AlterDatabaseEvent extends BaseDatabaseEvent {
        CatalogDatabase newDatabase();
        boolean ignoreIfNotExists();
    }

    /* Event for dropping database. */
    @PublicEvolving
    public class DropDatabaseEvent extends BaseDatabaseEvent {
        boolean ignoreIfExists();
    }

    /* Base table event, provides column list, primary keys, partition keys, watermarks and properties in CatalogBaseTable. The table can be source or sink. */
    public abstract class BaseTableEvent extends BaseCatalogEventCatalogEvent {
        ObjectIdentifier identifier();  
        CatalogBaseTable table();
    }

    /* Event for table creation. */
    @PublicEvolving
    public class CreateTableEvent extends BaseTableEvent {
        boolean ignoreIfExists();
    }

    /* Event for altering table, provides all information in old table and new table. */
    @PublicEvolving
    public class AlterTableEvent extends BaseTableEvent {
        List<TableChange> tableChanges();
        boolean ignoreIfExists();
    }

    /* Event for dropping table. */
    @PublicEvolving
    public class DropTableEvent extends BaseTableEvent {
        boolean ignoreIfExists();   
    }
}

/* Factory for catalog listener. */
@PublicEvolving
public interface CatalogEventListenerFactory {
    public CatalogEventListener createListener(Configuration configuration, ClassLoader classLoader);
}

/* Add listeners in the catalog context. */
@PublicEvolving
public interface CatalogFactory {
    /** Add listeners in the context. */
    @PublicEvolving
    interface Context {
        /* Get the listeners from context if they are exists. */
        List<CatalogEventListener> listeners();
    }
}

/* Storage identifier for different physical table. */
@PublicEvolving
public class StorageIdentifier {
    /* ExternalStorage storagetype information such as kafka, hive, iceberg or paimon. */
    String type();

    /* Identifier which identify the unique physical table. */
    String identifier();

    /* Properties for the storage identifier, users can get value from different keys for different storages, such as broker and topic for kafka. */
    Map<String, String> properties();
}

/* Storage identifier factory is loaded with specific connector type and create {@link StorageIdentifier}. */
@PublicEvolving
public interface StorageIdentifierFactory {
    /* Create storage identifier for different connector type. */
    StorageIdentifier createDynamicTableStorage(Configuration config, ClassLoader classLoader);
}

@PublicEvolving
public interface CatalogTable {
    /* Get physical storage identifier for the table. */
    StorageIdentifier storage();
}